insanity

I think the big danger of madness is not madness itself, but the habit of madness. What I discovered during the time I spent in the asylum is that I could choose madness and spend my whole life without working, doing nothing, pretending to be mad. It was a very strong temptation..

'But I don't want to go among mad people,' Alice remarked.'Oh, you can't help that,' said the Cat: 'we're all mad here. I'm mad. You're mad.''How do you know I'm mad?' said Alice.'You must be,' said the Cat, 'or you wouldn't have come here.'

Lewis Carroll (1832 - 1898)

Source: Alice's Adventures in Wonderland and Through the Looking Glass, Pages: Chapter 6